Positioning device for a drain pipe in a drying cylinder

ABSTRACT

A device for positioning a drain pipe ( 6 ) of a draining system in a drying cylinder ( 1 ) the jacket ( 2 ) of which has inner circumferential grooves ( 3 ) for condensate which is formed as a result of heat transfer, said draining system comprising an outlet means and a plurality of drain pipes which are connected to the outlet means, wherein the draining system removes the condensate from the grooves via the drain pipes and the outlet means, wherein the device has a pipe positioner ( 40 ) which is disposed within an end portion ( 9 ) of the drain pipe located closest to the jacket, said pipe positioner comprising a supporting body ( 41 ) resting on the top surfaces ( 30 ) of two adjacent ridges ( 5 ), and a locking device ( 54 ) for fixing the drain pipe to the pipe positioner ( 40 ), which has a first through hole ( 48 ) for receiving the drain pipe ( 6 ), and a second hole ( 49 ) for receiving the locking device, said second hole opening into the first hole. According to the invention, the first hole ( 48 ) is disposed in the supporting body, wherein the portion ( 51 ) of the locking device that is located in the supporting body is provided with a third through hole ( 52 ), interacting with and being aligned with the first hole of the supporting body, so that the drain pipe extends through both the supporting body and the locking device, wherein the locking device encloses the drain pipe ( 6 ) and is brought to a locked position in interaction with supporting body ( 41 ).

The present invention relates to a device for positioning a drain pipeof a draining system which is arranged in a steam-heated drying cylinderof a paper machine, said drying cylinder having a jacket, which on itsinside has circumferential grooves for collecting condensate that isformed as a result of heat transfer through the jacket to the outsidethereof, said draining system comprising an outlet means, whichdischarges on the outside of the drying cylinder, and a plurality ofdrain pipes which are arranged in a plurality of axial groups andconnected to the outlet means, said draining system being adapted toremove the condensate from said grooves of the drying cylinder to theoutside thereof via said plurality of drain pipes and outlet means, saiddevice comprising a first pipe positioner which is disposed within anend portion of the drain pipe located closest to the jacket, said pipepositioner comprising a supporting body which is designed for resting onthe top surfaces of two ridges located adjacent to each other, and alocking device for fixing the drain pipe to the pipe positioner, whereinthe pipe positioner is provided with a first through hole for receivingthe drain pipe, and a second hole for receiving the locking device, saidsecond hole opening into the first hole.

A known positioning device has a pipe positioner with a transversesupporting body for abutting against two adjacent ridges, delimiting thejacket groove, and a carrying body which projects perpendicularly fromthe supporting body to be received in the groove. At its lower endportion, the carrying body is provided with a smooth through hole forreceiving the drain pipe. A threaded hole extends from the top side ofthe supporting body downward therethrough and further through thecarrying body all the way to the said smooth hole. A locking device,comprising a threaded rod, is screwed into the threaded hole forabutting against the drain pipe and locking it in the desired positionfor the drain pipe, said position being locked by means of a locking nutcarried by the threaded rod. The known pipe positioner, thus having aT-shape, is made for use in a groove of a particular depth. A differentgroove depth thus requires a T-shaped pipe positioner whose carryingbody is shorter or longer in dependence on said groove depth, which is aproblem particularly with respect to the stock-keeping of several setsof pipe positioners, where each set has its own, particular dimension.

The object of the present invention is to achieve an improvedpositioning device for drain pipes which eliminates the above-mentionedproblems, and which enables it to be used for all drying cylinderregardless of the depth of the grooves on the inside of the jacket.Thereby, the stock-keeping is reduced to only one set of the pipepositioner in question.

The positioning device according to the invention is characterized inthat said first hole is disposed in the supporting body and that theportion of the locking device that is located in the supporting body isprovided with a third through hole adapted to interact with and bealigned with the first hole of the supporting body, so that the drainpipe extends through both the supporting body and the locking device,wherein the locking device is adapted to enclose the drain pipe and bebrought to a locked position in interaction with the supporting body, inwhich locked position the drain pipe, the supporting body and thelocking device are fixed to each other.

The invention will be described more closely with reference to thedrawings.

FIG. 1 is an end view of portions of a drying cylinder whose end wallhas been removed, and shows two out of several positioning devicesaccording to the invention of a draining system for condensate.

FIG. 2 shows the positioning devices in cross-section.

FIG. 3 shows one of the positioning devices, comprising a drain pipe andfirst and second pipe positioners, before mounting onto a collectingpipe of the draining system.

FIG. 4 shows the second pipe positioner in cross-section.

FIG. 5 shows the first pipe positioner in cross-section.

FIGS. 6 and 7 show the first pipe positioner with its different partsseparated.

FIG. 8 is a cross-section of the second pipe positioner before mountingaccording to FIG. 3.

FIG. 9 is a cross-section of the jacket of the drying cylinder, alongthe line XI-XI in FIG. 3, and shows the drain pipe and the first pipepositioner.

FIGS. 1 and 2 show an interior section of a steam-heated drying cylinder1, which is installed in a drying section of a paper machine formanufacturing a paper web. The drying cylinder has a jacket 2, which hasan outside, on which the paper web is dried, and an inside that isprovided with a plurality of endless, circumferential grooves 3, evenlydistributed in an axial direction, whose centres coincide with thecentre axis of the drying cylinder 1. Suitably, the grooves 3 have around, concave bottom surface 4. The grooves 3 define ridges 5 betweenthem, wherein the top surfaces 30 of the ridges 5 and the bottomsurfaces 4 and lateral walls of the grooves 3 together form an innerjacket surface for heat transfer. Such internally grooved dryingcylinders 1 are used, inter alia, in the drying section of a tissuepaper machine for manufacturing tissue paper, and then have a relativelylarge diameter which can vary from one machine to another. Furthermore,the drying cylinder 1 has a hollow central hub and two opposite axlejournals, which are connected to the central hub to extend out throughthe opposite lateral end walls of the drying cylinder 1. The dryingcylinder 1 is rotatably journalled by means of the axle journals, whichthus define the axis of rotation of the drying cylinder 1.

The energy for drying the paper web is supplied in the form of steam tothe interior space of the drying cylinder 1. The steam condenses on theinner jacket surface, and the heat is conducted through the jacket 2 toits outside, with which the paper web is in contact. During operation,condensate in the form of a film is accumulated on the bottom surface ofeach groove 3, said condensate film primarily determining the transitionresistance from steam to jacket. An efficient heat flow requires thatthe grooves 3 are kept as free as possible from condensate. A specialdraining system for condensate, comprising a plurality of elongateddrain pipes 6 which commonly are called suction pipes and are arrangedin a plurality of evenly distributed groups around the inside of thejacket 2, is used for draining each groove 3 from condensate asefficiently as possible. Furthermore, the draining system comprises anoutlet means which comprises, in order, a plurality of axially arrangedcollecting pipes 7, a stand pipe from each collecting pipe 7, a commoncentre connection for the stand pipes through said central hub andthrough one of the axle journals to the outside of the drying cylinder 1for further transport. Accordingly, the number of collecting pipes 7corresponds to the number of said groups. The collecting pipes 7 arearranged eccentrically and axially relative to the centre axis of thedrying cylinder 1.

Each drain pipe 6 has an end portion 9 having an open end 10, with whichthe space 11 of the groove 3 stands in open communication, and an endportion 12 having an open end 13 that opens into the collecting pipe 7,see FIG. 2. During operation, the opening 10 of the end portion 9 shouldbe disposed at a predetermined distance from the bottom surface 4 of thegroove 3, as is evident from FIGS. 1 and 9.

Each drain pipe 6 is provided with a device for positioning the drainpipe 6 relative to the inside of the jacket 2, and more preciselyrelative to the bottom surface 4 of the groove 3, in order to maintainsaid predetermined distance.

The positioning device comprises a first pipe positioner or pipeposition adjuster 40, which is disposed in said end portion 9 of thedrain pipe 6 that is located closest to the jacket 2. The first pipepositioner 40 comprises a supporting body 41, which is designed forresting on the top surfaces 30 of two successive ridges 5 to extend in adirection transversely across the groove 3 located therebetween. Thesupporting body 41 is delimited by two end surfaces 42, 43 facing awayfrom each other, two lateral surfaces 44, 45 facing away from eachother, an upper surface 46 and a lower surface 47, said lateral surfaces44, 45 and upper and lower surfaces 46, 47 extending between said endsurfaces 42, 43. Preferably, at least the lower surface 47 is curved asshown, e.g. circular-cylindrically. A first imaginary plane extendsthrough the end surfaces 42, 43 and the upper and lower surfaces 46, 47.A second imaginary plane extends through the two end surfaces 42, 43 andthe two lateral surfaces 44, 45 and intersects the said first plane atright angles. The planes may define centre planes of the supporting body41, but one of the planes, or both, may be located slightly to the sideof said centre plane.

A first through hole 48 extends between the lateral surfaces 44, 45 andhas a diameter that is slightly larger than the diameter of the drainpipe 6 for receiving the drain pipe 6 therein with a sliding fit, sothat the supporting body 41 can be displaced along the drain pipe 6 to adesired position relative to the end 10 of the end portion 9 of thedrain pipe 6, or alternatively said fulcrum of the drain pipe 6. Thefirst hole 48 has a centre axis that coincides with said second plane.Furthermore, a second through hole 49 is adapted to extend between theupper surface 46 and the lower, curved surface 47, said second hole 49having a larger diameter than the first hole 48. The second hole 49 hasa centre axis that coincides with said first plane. The centre axes ofthe two holes 48, 49 intersect each other at right angles, and theircommon intersection point coincides with the intersection point of thetwo said planes.

The first pipe positioner 40 further comprises a multi-functional,elongated pin 50, which comprises a central portion 51 that is designedto be received in the said second hole 49 with a sliding fit, whereinthe portion 51 thus has diameter that is slightly smaller than thediameter of the second hole 49. The said portion is provided with adiametrical through hole 52, which has the same diameter as the first,smaller hole 48 of the supporting body 41 to thereby be aligned with thelast-mentioned hole 48, so that the drain pipe 6 can be inserted intothe smaller hole 48 of the supporting body 41 from one end and furtherthrough the hole 52 of the pin portion, and then further through thesmaller hole 48 of the supporting body 4 and out through its other end.In that way, a unit is produced which is slidable along the drain pipe 6to be displaced and set to the desired position, when a predetermineddistance between the bottom 4 of the groove 3 and the open end 10 of thedrain pipe 6 has been reached. Furthermore, the pin 50 comprises a lowerguiding and supporting portion 53, which extends from the lower surface47 to be received in the groove 3 with the purpose of guiding andsupporting the pipe positioner 40 in the groove, so that the drain pipe6 is maintained in the correct, aligned position.

The length of the guiding and supporting portion 53 is smaller than thedepth of the groove 3. The first pipe positioner 40 further comprises alocking device 54 for locking the three structural members 6, 41, 50 toeach other. Such a locking device 54 can be designed and arranged in aplurality of different ways. In the shown embodiment, it comprises a nut55 and an upper, threaded portion 56 of the pin 50, projecting from theupper surface 46 of the supporting body 41, onto which threaded portionthe nut 55 is screwed, to finally abut against the upper surface 46 ofthe supporting body 41 and be tightened so that the supporting body 41,the drain pipe 6 and the pin 50 are locked to each other. If a positionadjustment has to be made, the nut 55 needs to be loosened one or a fewturns until the engagement is released, so that the first pipepositioner 40 can be displaced along the drain pipe in the desireddirection. The first pipe positioner 40 according to the inventionenables it to be used for all drying cylinders 1 regardless of the depthof the grooves 3 on the inside of the jacket 2. In order to reduce theweight of the supporting body 41, it can be provided with recesses, onboth sides of the hole 49 and extending downward a suitable distance ina direction from the upper surface 46, e.g. half of the distance down tothe lower surface.

The device further comprises a second pipe positioner or pipe positionadjuster 14, which is disposed in the end portion 12. The second pipepositioner 14 comprises a mounting device 15, see FIGS. 3 and 4, formounting the drain pipe 6 onto the collecting pipe 7, and a lockableconnection 16 that connects the drain pipe 6 to the mounting device 15.In the shown preferred embodiment, said connection 16 is a lockablejoint connection which, in an unlocked condition, articulately connectsthe drain pipe 6 to the mounting device 15. The joint connection 16forms a fulcrum for pivoting of the drain pipe in at least one verticalplane, i.e. a plane coinciding with the centre plane of the groove 3that intersects the centre axis of the drying cylinder 1 at rightangles. The degree of said pivoting is made in dependence on thediameter of the drying cylinder 1 and the depth of the groove 3, so thatan open end of the drain pipe 6 comes to be located at a predetermineddistance from the bottom surface 4 of the groove 3. Thereby, the jointconnection 16 comprises an inner joint body 17, see FIG. 3, which ispermanently mounted, e.g. by means of welding, onto the drain pipe 6 ata predetermined distance from said open end 10 of the said end portion 9of the drain pipe 6. The inner joint body 17 is designed with a curved,outer joint surface 18, which comprises surface portions 19, 20 at leastfacing forward and backward, as seen in the longitudinal direction ofthe drain pipe 6 and in a direction toward the collecting pipe 7.Furthermore, the joint connection 16 comprises an outer joint body 21,consisting of a first portion 22 and a second portion 23, see FIGS. 3and 4, which are detachably connected to each other and which togetherenclose the inner joint body 17. Each joint body portion 22, 23 isprovided with an inner joint surface 24 and 25, respectively, see FIG.4, which has the same shape and same radius as the joint surface 18 ofthe inner joint body 17. The two joint body portions 22, 23 are adaptedto be joined into a unit, i.e. into said outer joint body 21, whereintheir curved, inner joint surfaces 24 facing each other are adapted tointeract with the curved joint surface 18 of the inner joint body 17 toproduce in a first, initial position, a slidable interaction between thejoint surfaces 18, 24, 25 facing each other, in which initial positionthe drain pipe 6 has a possibility to pivot about said fulcrum, which isthus defined by the joint surfaces 18, 24, 25, as has been describedabove. If continuing the forced bringing together of the two joint bodyportions 22, 23 in a direction toward each other, the friction betweenthe joint surfaces 18, 24, 25 facing each other increases, until acompletely locked condition of the joint connection 16 is achieved,whereby the drain pipe 6 becomes fixed against pivoting about saidfulcrum. Suitably, the mounting device 15 and the joint body portion 22located closest to the joint body 17 are made in one piece, as isevident from FIGS. 3 and 4. The mounting device 15 and the outer jointbody 21 have axially through-going centre holes 31, 32, see FIG. 4,which have a larger diameter than the drain pipe 6 to thereby enablesaid pivoting of the drain pipe 6.

In the shown preferred embodiment of the lockable joint connection 16,it is constituted of a ball joint, wherein the said curved jointsurfaces 18, 24, 25 are spherical, whereby the draining means becomespivotable in all directions. The mounting device 15 for mounting thedrain pipe 6 onto the collecting pipe 7 comprises an externally threadedsleeve for screwing into an internally threaded hole 26 in a wall of thecollecting pipe 7, said threaded hole connecting to the interior of thecollecting pipe 7. The centre axis of the hole 26 is directed toward theregion of the groove 3, where the drain pipe 6 is to suck condensate. Itwill be appreciated that all mounting holes 26 of the collecting pipe 7have their centre axes aligned in the same way toward theircorresponding regions, which thus will be located on, and intersectedby, a common axial line. A screw depth stop 27 is formed at thetransition to the ball joint 16. The first joint member portion 22 iscylindrical and has an external thread. In the shown embodiment, thisfirst joint body portion 22 and said sleeve 15 are designed in onepiece, wherein said screw stop 27 is formed by a radial, circumferentialsurface at the transition therebetween in that the first joint bodyportion 22 has a larger diameter than the sleeve 15. The second jointbody portion 23 has the shape of a nut, having an internal thread and adiameter at this thread portion which are adapted to the outer diameterof the first joint body portion 22 and its thread, so that the nut 23can be screwed onto the first joint body portion 22 for the formation ofscrew connection while enclosing the inner spherical joint body 17. Theside of the nut 23 facing away from the thread portion has a wall 28that is provided with a centre hole 29, through which the drain pipe 6extends and which also allows that a small portion of the inner,spherical joint body 17 can project therefrom to thereby enable that thedrain pipe 6 can be pivoted in the desired way, when the ball joint isin a loosened state. The reference numeral 36 designates a securingplate, which is carried by the sleeve 15 and is foldable down over thenut 23 so that it is locked against being loosened, as is evident fromFIGS. 1-4.

Hitherto, a device with a second pipe positioner has been used where theend portion of the drain pipe facing toward the outlet means, and moreprecisely toward a collecting pipe, is provided with an external threadfor screwing the drain pipe into the mounting device, which has acorresponding internal thread. Furthermore, the threaded portion of thedrain pipe carries a locking nut, which is adapted to be brought intolocking abutment against the mounting device, when the position of thedrain pipe relative to the bottom surface of the groove has beendecided. The position of the drain pipe relative to the bottom surfaceof the groove is thus set and adjusted by a rotation of the drain pipeabout its axis so that it is screwed into or out of the mounting device.A disadvantage of the known device is that the length of the drain pipeis adapted to a particular drying cylinder and its diameter. Therefore,a range of drain pipes has to be provided for each size of dryingcylinder, with respect to their diameters. Another disadvantage is thatthe mounting of the drain pipe is inconvenient and time-consuming inthat it has to be performed directly inside the drying cylinder, and,furthermore, in that the adjustment of the drain pipes has to be doneone by one without being able to utilize the settings of a previous,already mounted drain pipe.

The second pipe positioner 14, included in a preferred embodiment of thedevice according to the invention, enables one and the same length ofthe drain pipe 6 to be used for drying cylinders 1 having differentdiameters in that the second pipe positioner 14 is pivoted relative tothe mounting axis 33, see FIG. 3, which is defined by the mountingdevice 15 that is fixed to the collecting pipe 7, so that the centreaxis 34 of the drain pipe 6, see FIG. 3, forms an obtuse angle with themounting axis 33, wherein the centre axis 34 thus may extend downward,as is shown in FIG. 3, or upward relative to the fixed mounting axis 33.In both cases, the centre axis 34 forms an acute angle a, see FIG. 3,with its tangent 35 in the intersection point with the bottom surface 4of the groove 3 (or with the outside of the jacket 2). The mounting ofthe drain pipes 6 can be performed in a faster, simpler and moreconvenient way in that it is only necessary to mount a first drain pipe6 onto the collecting pipe 7, and thereby to set a desired angle, whichis fixed by the nut 23 of the ball joint 16, whereafter the mountingdevice 15 is once again detached from the collecting pipe 7 to be usedas a template for setting the corresponding angle of the other drainpipes 6 of the collecting pipe 7, which operation consequently can becarried out outside of the drying cylinder 1, whereafter the thuspre-positioned drain pipes 6 with associated devices can be mounted ontothe collecting pipe 7 inside the drying cylinder 1. If an adjustment ofan angle has to be made, this is a simple operation of loosening the nut23 of the ball joint 16 to enable pivoting of the drain pipe 6 up ordown depending on the degree of required adjustment. In theabove-mentioned operations, the correct angle has been achieved when theopen end 10 of the drain pipe 6 facing toward the jacket 2 is located ata predetermined distance from the bottom surface 4 of the groove 3. Thisdistance is normally 3-5 mm. This distance is made permanent by means ofthe first pipe positioner 40, which is already pre-positioned on thedrain pipe 6, but which can be readjusted if necessary. Furthermore, thefirst pipe positioner 40 is necessary for absorbing the centrifugalforces acting on the drain pipe 6 during operation, and which otherwisewould press the end portion 9 of the drain pipe 6 inward in a directiontoward the bottom surface 4 of the groove 3.

In the described embodiment having a ball joint 16, the fulcrum of thedrain pipe 6 is thus defined by the centre point of the spherical jointsurface 18 of the ball joint 16. In an alternative embodiment of thejoint connection 16, the joint surface is cylindrical, defining ahorizontal centre axis, which thus constitutes the fulcrum of the drainpipe 6.

The first pipe positioner, of course, can be used in combination withany type of the second pipe positioner, e.g. the known design which hasbeen described above, where the end portion of the drain pipe facingtoward the outlet means, and more precisely toward a collecting pipe, isprovided with an external thread for screwing the drain pipe into themounting device, which has a corresponding internal thread, or the newdesign, described more closely above, having a pivotable mounting of thedrain pipe, which is preferred due to its many advantages over the saidknown design.

1-8. (canceled)
 9. A device for positioning a drain pipe (6) of adraining system which is arranged in a steam-heated drying cylinder (1)of a paper machine, said drying cylinder (1) having a jacket (2), whichon its inside has circumferential grooves (3) for collecting condensatethat is formed as a result of heat transfer through the jacket (2) tothe outside thereof, said draining system comprising an outlet means,which discharges on the outside of the drying cylinder (1), and aplurality of drain pipes (6) which are arranged in a plurality of axialgroups and connected to the outlet means, said draining system beingadapted to remove the condensate from said grooves (3) of the dryingcylinder (1) to the outside thereof via said plurality of drain pipes(6) and outlet means, said device comprising a first pipe positioner(40) which is disposed within an end portion (9) of the drain pipe (6)located closest to the jacket (2), said pipe positioner (40) comprisinga supporting body (41) which is designed for resting on the top surfaces(30) of two ridges (5) located adjacent to each other, and a lockingdevice (54) for fixing the drain pipe (6) to the pipe positioner (40),wherein the pipe positioner is provided with a first through hole (48)for receiving the drain pipe (6), and a second hole (49) for receivingthe locking device (54), said second hole (49) opening into the firsthole (48), wherein: said first hole (48) is disposed in the supportingbody (41); and the portion (51) of the locking device (54) that islocated in the supporting body (41) is provided with a third throughhole (52) adapted to interact with and be aligned with the first hole(48) of the supporting body (41), so that the drain pipe (6) extendsthrough both the supporting body (41) and the locking device (54),wherein the locking device (54) is adapted to enclose the drain pipe (6)and be brought to a locked position in interaction with the supportingbody (41), in which locked position the drain pipe (6), the supportingbody (41) and the locking device (54) are fixed to each other.
 10. Thedevice according to claim 9, wherein the second hole (49) for thelocking device (54) intersects the first hole (48) and is through-going,and the locking device (54) comprises a lower, free guiding andsupporting portion (53) which is adapted to project from the supportingbody (41) to be freely received in the jacket groove (3).
 11. The deviceaccording to claim 9, said device further comprising a second pipepositioner (14) that is disposed in an end portion (12) of the drainpipe (6) located closest to said outlet means, said pipe positioner (14)comprising a mounting device (15) for mounting the drain pipe (6) ontothe outlet means, and a lockable connection (16) that connects the drainpipe (6) to the mounting device (15),wherein said lockable connection(16) is a joint connection, which defines a fulcrum for pivoting of thedrain pipe (6) in at least one vertical plane to enable positioning ofthe drain pipe (6) relative to the bottom surface (4) of the groove (3).12. The device according to claim 11, wherein the degree of saidpivoting is made in dependence on the diameter of the drying cylinder(1) and the depth of the groove (3), so that an open end (10) of thedrain pipe (6) comes to be located at a predetermined distance from thebottom surface (4) of the groove (3).
 13. The device according to claim11, wherein the joint connection (16) comprises: an inner joint body(17) which is fixedly arranged on the drain pipe (6) at a predetermineddistance from the open end (13) of the end portion (12), and which isdesigned with a curved joint surface (18); and an outer joint body (21)that consists of a first portion (22) and a second portion (23), whichare detachably connected to each other and which together are adapted toenclose the inner joint body (17), said joint body portions (22, 23)having inner joint surfaces (24, 25), which are adapted to the jointsurface (18) of the inner joint body (17) for slidable interactionduring said pivoting of the drain pipe (6) and for locking frictionalinteraction in each set position of the drain pipe (6).
 14. The deviceaccording to claim 13, wherein the mounting device (15) and the bodyportion (22) of the outer joint body (21) located closest thereto aremade in one piece.
 15. The device according to claim 13, wherein themounting device (15) and the outer joint body (21) have axiallythrough-going center holes, which have a larger diameter than the drainpipe (6) to thereby enable said pivoting of the drain pipe (6).
 16. Thedevice according to claim 11, wherein the lockable joint connection (16)is a ball joint with spherical joint surfaces (18, 24, 25).